Adjustable shotgun choke

Abstract

The present invention is a light weight low profile variable shotgun bore choke that is easily manually adjusted by the user. To minimize the choke profile, the choke is connected to the shotgun through a threaded connection within the muzzle bore. External threads on a choke inner sleeve are configured to mate with standard threads found in existing prior shotgun barrel muzzles or with custom threads specifically formed. By using a threaded connection internal to the gun barrel, the overall radial dimensions of the choke are minimized thereby reducing the profile visible to the user. Weight is also reduced by a design which reduces radial dimensions and by use of light weight materials. The choke is adjusted by the user by manually rotating an outer adjustment sleeve with respect to an inner bore sleeve which is fixed to the shotgun barrel. The adjustment sleeve rotates through a range of choke conditions between two physical stops. Various choke conditions are indicated by circumferential grooves that are easily viewed from any location around the choke.

I claim:  
     
       1. An improved adjustable low profile shotgun choke for attachment to shotguns having internal threads within the shotgun muzzle, the choke comprising: 
       an inner sleeve having a bore and having:  
       a first end and second end,  
       first external threads adjacent the first end,  
       a plurality of separated longitudinal fingers adjacent the second end,  
       second external threads between the first and second end;  
       an adjustment sleeve having inner threads engaged with the inner sleeve second external threads and the adjustment sleeve having a tapered inner adjustment surface, the adjustment surface contacting the flexible fingers, such that when the adjustment sleeve is rotated about the inner sleeve, the adjustment surface forces the fingers into a more converging condition;  
       a first and second stop limiting rotation of the adjustment sleeve with respect to the inner sleeve at a minimum and maximum choke position, respectively.  
     
     
       2. The choke of  claim 1 , wherein: 
       the first stop comprises:  
       a resilient clip between the inner sleeve and adjustment sleeve, the clip rotationally connected to the inner sleeve, and the clip having a clip end biased toward the adjustment sleeve; and  
       the adjustment sleeve has an aperture receiving, in an open condition, the clip end such as prevent the adjustment sleeve from rotating past the open condition.  
     
     
       3. The choke of  claim 1 , further comprising: 
       indicia configured to indicate the position of the adjustment sleeve and visible from any radial position relative to the choke.  
     
     
       4. The choke of  claim 3 , wherein: 
       the indicia consists of at least one circumferential groove.  
     
     
       5. The choke of  claim 4 , wherein: 
       the choke is configured for a 12 gauge shotgun; and  
       the choke has a maximum radial dimension of one inch.  
     
     
       6. The choke of  claim 5 , wherein: 
       the adjustment sleeve is formed substantially from titanium.  
     
     
       7. An improved shotgun having a removable choke capable of delivering shot in variable patterns, comprising: 
       a shotgun body having a barrel mouth having internal threads, and secured to the internal threads the device of  claim 1 .